Trajectories of Retention in Opioid Agonist Therapy and Overdose Risk During a Community-Wide Overdose Epidemic in a Canadian Setting.

Abstract

INTRODUCTION:

Retention in opioid agonist therapy consistently has been linked with improved outcomes among people with opioid use disorder. However, less is known about the links between patterns of engagement in opioid agonist therapy over the long term and overdose risk. This study assesses the association of opioid agonist therapy retention trajectories with nonfatal overdose.

METHODS:

Data were drawn from 2 community-recruited prospective cohorts of people who use drugs in Vancouver, Canada. Latent class growth analysis was used to identify trajectories of opioid agonist therapy retention among people with opioid use disorder initiating therapy, and generalized estimating equations assessed the association of these trajectories with nonfatal overdose events after opioid agonist therapy initiation.

RESULTS:

Between 2005 and 2018, among 438 opioid agonist therapy initiators, 4 retention trajectories were identified: consistently high (35.6%), increasing (26.0%), consistently low (23.3%), and decreasing (15.1%) opioid agonist therapy engagement. During the study period, there were 371 nonfatal overdose events, with 179 (40.1%) participants reporting ≥1. In adjusted analysis, the consistently low (AOR=1.73, 95% CI=1.10, 2.71) and decreasing (AOR=1.87, 95% CI=1.18, 2.95) retention trajectories were positively associated with increased odds of nonfatal overdose compared with the consistently high opioid agonist therapy retention class.

CONCLUSIONS:

Suboptimal trajectories of opioid agonist therapy retention were associated with an increased likelihood of nonfatal overdose. These findings suggest that reducing the barriers to sustained engagement in opioid agonist therapy will be critical to address North America's overdose epidemic.

• Authors: M Eugenia Socías, Huiru Dong, Evan Wood, Seonaid Nolan, Kanna Hayashi, Thomas Kerr, M-J Milloy
• Journal: American journal of preventive medicine (Am J Prev Med) Vol. 60 Issue 1 Pg. 57-63 (01 2021) ISSN: 1873-2607 [Electronic] Netherlands
• PMID: 33341181 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2020 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Chemical References

• Analgesics, Opioid

Topics

• Analgesics, Opioid (therapeutic use)
• Canada
• Drug Overdose (drug therapy, epidemiology)
• Epidemics
• Humans
• Opioid-Related Disorders (drug therapy, epidemiology)
• Prospective Studies